Xojo Plugin
REST Stream Multipart Body from File

Demonstrates how to send a multipart/form-data HTTP request, where one of the parts contains data streamed directly from a file. This is good for cases where the file to be uploaded is very large.
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Xojo Plugin
Dim success As Boolean
success = False

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Dim rest As New Chilkat.Rest

// Connect to the destination web server.
Dim bTls As Boolean
bTls = True
Dim port As Int32
port = 443
Dim bAutoReconnect As Boolean
bAutoReconnect = True
success = rest.Connect("www.somewebserver.com",port,bTls,bAutoReconnect)

// This example will send the following multipart/form-data request.
// The Content-Length is automatically computed and added by Chilkat.

// 	POST /some_path HTTP/1.1
// 	Content-Type: multipart/form-data; boundary=---------------------------735323031399963166993862150
// 	Content-Length: 834
// 
// 	-----------------------------735323031399963166993862150
// 	Content-Disposition: form-data; name="text1"
// 
// 	text 123 abc
// 	-----------------------------735323031399963166993862150
// 	Content-Disposition: form-data; name="text2"
// 
// 	xyz
// 	-----------------------------735323031399963166993862150
// 	Content-Disposition: form-data; name="file1"; filename="a.txt"
// 	Content-Type: text/plain
// 
// 	Content of a.txt.
// 
// 	-----------------------------735323031399963166993862150
// 	Content-Disposition: form-data; name="file2"; filename="a.html"
// 	Content-Type: text/html
// 
// 	<!DOCTYPE html><title>Content of a.html.</title>
// 
// 	-----------------------------735323031399963166993862150
// 	Content-Disposition: form-data; name="file3"; filename="starfish.jpg"
// 	Content-Type: image/jpeg
// 
// 	binary data goes here
// 	-----------------------------735323031399963166993862150--

// Set the Content-Type for the topmost MIME part.
success = rest.AddHeader("Content-Type","multipart/form-data")

// Specify each part of the request.
rest.PartSelector = "1"
success = rest.AddHeader("Content-Disposition","form-data; name=""text1""")
success = rest.SetMultipartBodyString("text 123 abc")

rest.PartSelector = "2"
success = rest.AddHeader("Content-Disposition","form-data; name=""text2""")
success = rest.SetMultipartBodyString("xyz")

rest.PartSelector = "3"
success = rest.AddHeader("Content-Disposition","form-data; name=""file1""; filename=""a.txt""")
success = rest.AddHeader("Content-Type","text/plain")
success = rest.SetMultipartBodyString("Content of a.txt.")

rest.PartSelector = "4"
success = rest.AddHeader("Content-Disposition","form-data; name=""file2""; filename=""a.html""")
success = rest.AddHeader("Content-Type","text/html")
Dim sbHtml As New Chilkat.StringBuilder
success = sbHtml.LoadFile("qa_data/html/a.html","utf-8")
success = rest.SetMultipartBodySb(sbHtml)

rest.PartSelector = "5"
success = rest.AddHeader("Content-Disposition","form-data; name=""file3""; filename=""starfish.jpg""")
success = rest.AddHeader("Content-Type","image/jpeg")

// When the request is sent, stream this part directly from the file.
// This avoids having to load the entire file into memory.
Dim fileStream As New Chilkat.Stream
fileStream.SourceFile = "qa_data/jpg/starfish.jpg"
success = rest.SetMultipartBodyStream(fileStream)

Dim responseBody As String
responseBody = rest.FullRequestMultipart("POST","/some_path")
If (rest.LastMethodSuccess <> True) Then
    System.DebugLog(rest.LastErrorText)
    Return
End If

// ...
// ...

// Clear the REST object for any subsequent requests..
success = rest.ClearAllHeaders()
success = rest.ClearAllParts()
rest.PartSelector = ""